Being in debt just means one owes money. The US government has assets and various investments. Being bankrupt is when you can't pay back your debt, which the US most likely will be able to do.
82 karma · joined August 31, 2014
In fact, the show was basically saying, "Hey, teaching needs to be more valued in our culture, because right now 'good' teachers can't afford what they need and feel discouraged."
Now, of course the meth-cooking was an exaggeration--and in no way is Walt excused for his actions (he had friends, family, and co-workers all offering to help)--but it was meant to show how trapped teachers felt.